This section is intended to provide a background or context to the invention recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
The present invention relates generally to the field of temperature-controlled display devices (e.g. refrigerated display devices or cases, etc.) having a temperature-controlled space for storing and displaying products such as refrigerated foods or other perishable objects. More specifically, the present invention relates to a control system for operating a temperature-controlled display device. More specifically still, the present invention relates to a control system for a temperature-controlled display device that uses sensory input from a proximity sensor integrated with the display case door handle to control conditions within the temperature-controlled space.
Temperature-controlled display devices (e.g., refrigerators, freezers, refrigerated merchandisers, refrigerated display cases, etc.) may be used in commercial, institutional, and residential applications for storing or displaying refrigerated or frozen objects. For example, refrigerated display cases can be used to display fresh food products (e.g., beef, pork, poultry, fish, etc.) in a supermarket or other commercial setting.
Refrigerated display cases typically include cooling elements (e.g. cooling coils, heat exchangers, evaporators, etc.) that receive a coolant (e.g. a liquid such as a glycol-water mixture, a refrigerant, etc.) from a cooling system (e.g., a refrigeration system) to provide cooling to the temperature-controlled space. Some refrigerated display cases include fans that can be used to move air over the cooling elements to facilitate heat transfer thereto. Fans may also be used to create an air barrier (e.g., an air curtain) to prevent outside air from entering the temperature-controlled space.
Some refrigerated display cases have doors that can be opened (e.g., by a customer) to access products within the temperature-controlled space. The position of the doors (i.e., open or closed) can be detected using a variety of well-known sensors. However, current refrigerated display cases are unable to anticipate when the doors are about to be opened and therefore are unable to preemptively implement different control strategies prior to the doors being physically opened.
Accordingly, it would be desirable to provide a refrigerated display device or case with the ability to detect when the doors are about to be opened that would overcome these and other disadvantages.